Manifold removal help?

[8683jb]

I decided to freshen up my engine so I started removing the manifolds today and it turned brown. All the bolts are removed or backed out except the two long upper bolts shared by both manifolds. I started soaking them with PB Blaster yesterday after I cleaned out the parting line between the manifolds so it would soak in for the length of the bolts. I tried backing them out with light pressure and tugs on a breaker bar, and for a while they acted like they were finally gonna turn, but this was a sick ruse! They broke off at the heads instead. The manifolds aren't even thinking about coming off with the remnants of those two bolts still attached. I made up a plate with a bolt and bolted it to the carb mounting pad so I could try to push against the head and push the manifolds away, but it's taking a lot more pressure than I'm comfortable with. I think the force is trying to tip the manifold down more than straight away. I'm thinking I might try to preload it with the bolt and then pull out on the bottom of the exhaust outlet to see if that will break it loose, but before I break something, has anyone else had this experience? I appreciate any suggestions or ideas.

[8683jb]

I got it. I turned a flat-faced driver on the lathe to fit into the broken bolt holes and to fit my rivet gun and with it turned up and with the jam bolt tightened against the cylinder head, pre-loading it, I fed the driver into the holes and alternately tapped hell out of the broken bolts - much like driving them out with a drift. A few seconds of that and then pre-loaded with the bolt some more and hit them again. I repeated that several times. Each time it moved about 1/8" and eventually it walked right off.